The Northern Pacific High Line Bridge No. 64, built between 1907 and 1908, has continued to perform yeoman service in the uninterrupted flow of the Nation's commerce. Nearly, 100 years after this bridge officially opened, it still carries 125-ton car unit coal trains, double stack container trains, lumber, and refined products at train speeds of 50 m.p.h.
Quicksand
YearAdded:
Image Credit: Original Photo: Public Domain; Produced prior to 1/1/1923Image Caption: Northern Pacific High Line Bridge No 64Era_date_from: 1908
2004
As one of the large strikes in the Lake Superior geological district, the Chapin Mine was located under a cedar swamp and unminable until it was drained by one of the largest pumping engines of the 1880s. Miners at the Chapin Mine, which began producing ore in 1880, soon tried to sink a deep shaft through 90 feet of quicksand, using enormous pumps driven by compressed air. The sand was frozen using two of the largest refrigeration compressors built, and a sectional cast-iron circular shell lined the D shaft. Mining continued for ten years using conventional pumps to dewater the lower levels.
YearAdded:
Image Credit: Public Domain; Produced prior to 1/1/1923Image Caption: Chapin Mine PumpEra_date_from: 1893
1987
Innovations
As one of the large strikes in the Lake Superior geological district, the Chapin Mine was located under a cedar swamp and unminable until it was drained by one of the largest pumping engines of the 1880s. Miners at the Chapin Mine, which began producing ore in 1880, soon tried to sink a deep shaft… Read More
The Northern Pacific High Line Bridge No. 64, built between 1907 and 1908, has continued to perform yeoman service in the uninterrupted flow of the Nation's commerce. Nearly, 100 years after this bridge officially opened, it still carries 125-ton car unit coal trains, double stack container…
Read More